Some types of storage, such as solid state storage, access and modify information at different levels of granularity depending upon the type of access. For example, read and write granularity in NAND Flash is at the page level, whereas erasure granularity is at the block level (where multiple pages comprise a single block). Another NAND Flash characteristic is that NAND Flash which already has some information stored in it must be erased before it can be programmed or written to again. This is because NAND Flash stores information in the form of voltage levels and the stored voltages can be incrementally increased or completely discharged, but incremental decreases in voltage are not possible.
As a result of the NAND Flash characteristics described above, current techniques require a significant number of accesses to the NAND Flash and/or a significant amount of processing, even if only a relatively small change to the block is desired. New techniques which reduce the amount of power and/or time required to make a change to already stored data would be desirable.